American College Of Surgeons - Inspiring Quality: Highest Standards, Better Outcomes

Your Breasts

Knowing about your breast structure will help you understand your cancer type and treatment.1

In women, the breasts are made up of

  • Nipple and areola (darker skin around the nipple)—on the outside of your breast
  • Lobules—the milk-producing glands
  • Ducts—carry the milk from the lobules to the nipple
  • Connective and fatty tissue—provides the structure of your breast
  • Muscle—supports your breast tissue
  • Blood vessels—arteries carry oxygen and nutrients to the breast and veins remove waste from the cells of your breast
  • Lymph vessels—carry lymph fluid, which contains infection-fighting white blood cells. The lymph vessels from your breast drain under the arm (axilla) and into your chest. Cancer cells can spread to other areas of your body through the lymphatic system.
  • Lymph nodes—the glands found along the lymph vessels. This is where the lymph is filtered. Abnormal cells are trapped in the lymph.
  • Sentinel lymph nodes—the nodes closest to the tumor site

Anatomy of the Female Breast